Imaging skull, bone, and lung imaging using multiple aperture ultrasound imaging

Abstract

A diagnostic ultrasound imaging method is provided, that can include transmitting an omni-directional unfocused ultrasound waveform into a target region with a transmit aperture of a multiple aperture ultrasound imaging probe; receiving ultrasound echoes from the target region with a plurality of receive apertures of the multiple aperture ultrasound imaging probe; with a processor of the multiple aperture ultrasound imaging probe, optimizing a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes; with the processor, beamforming the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance to obtain diagnostic 2D or 3D medical images; and presenting the diagnostic 2D or 3D medical images on a display.

Description

IMAGING SKULL, BONE, AND LUNG IMAGING USING MULTIPLE APERTURE ULTRASOUND IMAGINGPRIORITY CLAIM

[0001] This patent application claims priority to U.S. provisional patent application no. 63 / 583,103, titled “IMAGING SKULL, BONE, AND LUNG IMAGING USING MULTIPLE APERTURE ULTRASOUND IMAGING,” and filed on September 15, 2023, which is herein incorporated by reference in its entirety.INCORPORATION BY REFERENCE

[0002] Unless otherwise specified herein, all patents, publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.RELATED PATENTS AND APPLICATIONS

[0003] This application is also related to the following US Patent Applications: U.S. Patent No. 8,007,439, titled "Method and Apparatus to Produce Ultrasonic Images Using Multiple Apertures"; U.S. Patent No. 9,247,926, titled "Multiple Aperture Medical Ultrasound Transducers"; U.S. Patent No. 9,146,313, titled "Point Source Transmission and Speed-of- Sound Correction Using Multi -Aperture Ultrasound Imaging"; U.S. Patent No. 9,668,714, titled "Systems and Methods for Improving Ultrasound Image Quality by Applying Weighting Factors"; U.S. Patent No. 9,883,848, titled "Ultrasound Imaging Using Apparent Point- Source Transmit Transducer"; U.S. Patent No. 10,401,493, titled "Network- Based Ultrasound Imaging System"; U.S. Patent No. 11,253,233, titled “Calibration of Multiple Aperture Probes”; and U.S. Patent Publication No. 2017 / 0209121, titled "Ultrasound Imaging with Sparse Arrays"; U.S. Patent Publication No. 2023 / 024833, titled “Multiple Aperture Imaging Systems and Methods”; International Patent Application No. PCT / US 2020 / 05662, titled “Systems and Methods for Tissue Characterization Using Multiple Aperture Ultrasound”; International Patent Application No. PCT / US2021 / 57725, titled “Systems and Methods for Improving Ultrasound Image Quality”; International Patent Application No. PCT / US 2023 / 062069, titled “Synthetic Aperture Unfocused Transmission for Multiple Aperture Ultrasound Systems.” The entire contents of each of these patents and patent applications is incorporated herein by reference. These related applications may be referred to herein as “Applicant’s prior patents and applications.”FIELD

[0004] This invention generally relates to medical diagnostics and specifically to diagnostic data collected through the use of ultrasound.BACKGROUND

[0005] Medical ultrasound imaging has many significant diagnostic imaging uses. This modality is known to have barriers such as bone and gas that the user needs to have significant skill to work around. Often the desired target to be imaged is behind an obstacle that can be negated with accurate aiming of the transducer. For instance, the liver can be imaged subcostally by placing the transducer below the ribs and aiming “up” at the liver or intercostally by placing the transducer in-between the ribs to get a clear view of a section of the liver. That same level of expertise is required to conduct interventional procedures requiring the placement of instruments directly under and in-plane with an ultrasound transducer and so that therapies can be conducted under image guidance. Ribs and other obstacles often limit the plane of view. For instance, only the plane of view aligned with an intercostal space may be physically possible, yet the desired access to a lesion may require a different path not in alignment with the intercostal space. Similarly, imaging directly into the skull to access pathology for treatment may not be possible, and often a access port (hole) is cut in the skull so that a conventional ultrasound probe may be inserted for direct access to the brain. It would be greatly desirable not have to remove or avoid bone in order to perform the image guidance.

[0006] Similarly, medical ultrasound imaging users need to avoid gas filled obstacles. For instance, imaging the entire length of the pancreas is often “obscured” by portions of the gas filled stomach. Imaging the abdominal aorta can also be hindered by bowel gas, so the operators often push the transducer into the gut in an attempt to get closer to the aorta in hopes of being able to make a diagnosis.

[0007] These limitations to ultrasound are well known to those in the art.

[0008] However, it is possible to image tissue and pathology inside of bone and gas filled pockets with Ping Based Multiple Aperture (PMA) Imaging Systems as has been disclosed in many of the cited patents and applications herein. While the method of the core methods of Computed Echo Tomography on board PMA systems has been disclosed, further methods and apparatus enable enhanced imaging inside of bone, lung and other forms of dense or gas filled tissues.

[0009] This work is concerned with the devices and method of imaging into bone, dense tissue, lung and other gas filled tissues by a PMA system. Further, it addresses utilizing thatraw data for qualitative and quantitative analysis, and the use of algorithms to both train and assess that data.SUMMARY OF THE DISCLOSURE

[0010] A diagnostic ultrasound imaging method, comprising the steps of: transmitting an omni-directional unfocused ultrasound waveform into a target region with a transmit aperture of a multiple aperture ultrasound imaging probe; receiving ultrasound echoes from the target region with a plurality of receive apertures of the multiple aperture ultrasound imaging probe; with a processor of the multiple aperture ultrasound imaging probe, optimizing a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes; with the processor, beamforming the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance to obtain diagnostic 2D or 3D medical images; and presenting the diagnostic 2D or 3D medical images on a display.

[0011] In some aspects, the method comprises repeating the optimizing and beamforming steps for additional regions of interest within the target region.

[0012] In one aspect, the diagnostic 2D or 3D medical images include a plurality of regions of interest with varying frequency, voltage levels, and acoustic impedances based on the optimization for each region of interest.

[0013] In some aspects, the processor implements a trained machine learning model to perform the optimizing step.

[0014] A diagnostic ultrasound imaging method is provided, comprising the steps of: transmitting an omni-directional unfocused ultrasound waveform into a target region with a transmit aperture of a multiple aperture ultrasound imaging probe; receiving ultrasound echoes from the target region with a plurality of receive apertures of the multiple aperture ultrasound imaging probe; with a trained machine learning model of the multiple aperture ultrasound imaging probe, optimizing a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes; with a processor, beamforming the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance from the trained machine learning model to obtain diagnostic 2D or 3D medical images; and presenting the diagnostic 2D or 3D medical images on a display.

[0015] In some aspects, the region of interest is received as a user input.

[0016] A diagnostic ultrasound imaging method, is provided comprising the steps of: transmitting an omni-directional unfocused ultrasound waveform into a target region with atransmit aperture of a multiple aperture ultrasound imaging probe; receiving ultrasound echoes from the target region with a plurality of receive apertures of the multiple aperture ultrasound imaging probe; receiving an input from a user indicating a region of interest within the target region; with a trained machine learning model of the multiple aperture ultrasound imaging probe, optimizing a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes; with a processor, beamforming the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance from the trained machine learning model to obtain diagnostic 2D or 3D medical images; and presenting the diagnostic 2D or 3D medical images on a display.

[0017] In some aspects, the trained machine learning model is configured to identify one or more patterns in the echo data.

[0018] In one aspect, the trained machine learning model is configured to compare the one or more patterns to previously collected ultrasound echo data stored in a database.

[0019] An ultrasound imaging system is provided, comprising: at least one transmitting transducer element configured to transmit an omni-directional unfocused ultrasound waveform into a target region; a plurality of receiving transducer elements configured to receive ultrasound echoes from the target region; a processor configured optimize a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes, the processor being further configured to beamform the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance to obtain diagnostic 2D or 3D medical images.

[0020] In some aspects, the system includes a display configured to present the diagnostic 2D or 3D medical images on a display.BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The novel features of the invention are set forth with particularity in the claims that follow. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:

[0022] FIG. l is a schematic illustration of a multiple aperture imaging probe with multiple arrays.

[0023] FIG. 1 A is a schematic diagram of the arrays of the multiple aperture imaging probe conforming to the external portion of the tissue being imaged. The arrays being flexible enough to conform to the shape will be moved, or to be locked down to hold a specific shape.

[0024] FIG. 2 is a schematic diagram of an embodiment a concave curvilinear matrix with curvature in two orthogonal directions, also referred to as a Three Dimensional (3D) array. Each element in a 3D array is displaced relative to adjacent elements in all of x, y, and z axes. In this illustration, an element or elements of a transmit aperture is designated to insonify the medium. Multiple targets in the medium are illustrated for the purpose of demonstrating how volumetric data may be gathered. Multiple receive apertures are illustrated to demonstrated how simultaneous gathering of data may involve timing and tissue speed of sound adjustments. The array itself may be fixed or flexible. That is, it may conform to the area being imaged like a mat or patch.

[0025] FIG 3 A is an example of an enclosure for the transducer enabling ease of use for operators in the field.

[0026] FIG. 3B demonstrates the enclosure housing a ID or 1.5D array that may be adjustable or conforming.

[0027] FIG. 3C demonstrates the enclosure housing 2D or 3D array that may be adjustable or conforming.

[0028] FIG. 3D demonstrates the enclosure housing 2D or 3D array that may be adjustable or conforming using pMUT or cMUT transuducers.

[0029] FIG. 4 demonstrates both a side and end of a typical medical imaging piezoelectric array including several matching layers and a lens. Typical speeds-of-sound associated with those layers are also listed.

[0030] FIG. 5 demonstrates both a side and end of an ultrasound transducer with piezoelectric, pMUT or cMUT arrays including a single matching layers and a lens. Typical speeds-of-sound associated with those layers are also listed. This probe was specifically designed for imaging through and into bone.

[0031] FIG. 6 demonstrates both a side and end of an ultrasound transducer with piezoelectric, pMUT or cMUT arrays including a single matching layers and a lens. Typical speeds-of-sound associated with those layers are also listed. This probe was specifically designed for imaging through and into bone.

[0032] FIG. 7 is a representation of the exterior layers of the skull and scalp and associated average adult thickness.

[0033] FIG. 8 demonstrates the materials and construction of a 3 array Multiple Aperture Probe.

[0034] FIG. 9 demonstrates the location of higher speed matching layer locations on a desired probe for imaging through bone.

[0035] FIG 10 demonstrates the location of higher speed matching layer locations on a desired probe for imaging through bone.

[0036] FIG. 11 is a flowchart that describes a method for imaging through bone.

[0037] FIG. 12 shows a data set comprised of pixels or voxels, in this case as a 2D slice of pixels.DETAILED DESCRIPTION

[0038] The various embodiments will be described in detail with reference to the accompanying drawings. References made to particular examples and implementations are for illustrative purposes, and are not intended to limit the scope of the invention or the claims.

[0039] The present disclosure provides systems and methods for utilizing artificial intelligence to analyze raw data produced by ping-based multiple aperture imaging (“PMA” imaging) systems The resultant data can be used to improve image quality and to conduct quantitative or qualitative analysis of both visual and non-visual diagnostic conditions.

[0040] As described in more detail below and in Applicant’s prior patents and applications, PMA imaging involves transmission of ultrasound “pings,” echoes of which may be received by receive elements located at some distance from the transmitter. Each received echo signal lies along an ellipse defined by the transmitter and receiver positions and the time interval between ping transmission and echo reception. A data element can be created virtually anywhere in a 2D grid or 3D volume. Typically, ellipses crossing at a location in a 2D grid is known as a pixel. Ellipses crossing in a 3D volume are known as a voxel. An image may be formed by combining such pixels or voxels (i.e., data elements) in a way that their intersections become emphasized. Each intersection may be an image point in a two-dimensional or three-dimensional image. Concurrently and separately, groupings of data elements known as data sets may be evaluated for quantitative and or qualitative indications of diagnostic conditions.

[0041] FIG. 1 demonstrates a ping based multiple aperture probe 830, with arrays 504, 506, 508, 510 and 512, and one or more processors 801, 802, and 803 configured to control operation of the probe including transmission of ultrasound wavefronts from the arrays and receiving processing and storing echo data. Subarrays or often individual elements within each array. However, sub-arrays can be located across physical gaps between arrays andshould not be considered limited to individual elements on an individual array. As disclosures in other inventions cited herein, PMA system to do not require arrays to be in contiguous, flat or even in alignment. This is because PMA systems used unfocused transmissions and each receiver collects data independently. PMA systems operate at optimal performance when calibrated or ideally when calibrated dynamically in real time as is discussed in U.S. Patent No. 11,253,233.

[0042] Transducers may be contiguous in some embodiments or may configured using multiple arrays in other embodiments. No matter the type of array, transducer elements operate independently and can be utilized to form any number of either transmit or receive apertures within the structure. As used in the embodiment in FIG. 1, the terms "transducer array" or "array" generally refers to a collection of transducer elements mounted to a common backing plate. Such arrays may have one dimension (ID), two dimensions (2D), 1.5 dimensions (1.5D) or three dimensions (3D). Other dimensioned arrays as understood by those skilled in the art may also be used. Transducer arrays may also be collections of pMUT or cMUT transducer elements. An element of a transducer array may be the smallest discretely functional component of an array. For example, in the case of an array of piezoelectric transducer elements, each element may be a single piezoelectric crystal or a single machined section of a piezoelectric crystal.

[0043] FIG. 1 A then demonstrates the arrays 504-512, and emitting surfaces 812-820, respectively, being placed against tissue or an object and conforming to that shape. Electrical connection or wire 822 is shown coupled to each of the arrays. This is an ideal characteristic when the user needs to get the probe a uniquely shaped structure that changes shape as the transducer is moved across it. This would be the case for a skull, a break or even an extremity such as an arm or foot. The ability of the probe to conform, specifically in a concave manner, is beneficial in maintaining much needed skin contact throughout the examination. Additionally, the convex nature of the shape keeps the transducer elements nearer to the desired targets to be imaged.

[0044] FIG. 2 then is a representation of a 3D array. The represented 3D array 300 is concave around 2 different axes, hence placing individual elements in 3 -dimensional space relative to each other. As seen in FIG. 2, multiple transmit apertures T1 through TN are indicated for the purpose of demonstrating transmit pulses being received on one or more receive apertures R2 and / or R3. A single target 321 or reflector 321 is indicated within 3D volume 310 for the purpose of demonstrating how data may be gathered. The 3D array can be fixed in a desired concave shape for a specific type of anatomy, or it can be flexible. That is, an array can be made of a pliable MEMS material and placed into a transducer house as isshown in FIGS. 3A-3D. Or, the 3D array can be made of a mesh material and placed on the patient with an adhesive like bandage applicator. Finally, a probe used to collect 3D volumetric data sets need not be from a 3D array, instead a 2D array not curved around an axis, but having elements arranged in a straight rectangle or square can also be used to provide a 3D volume in a PMA system as well.

[0045] U.S. Patent No. 9,220,478, titled “Concave Ultrasound Transducers and 3DArrays” demonstrates many iterations of arrays configurations to produce volumetric data sets and their associated voxels. Illustration of FIG. 2 is presented here to represent a 3D array used with a PMA system to create 3D volumetric data sets. In FIG. 2, a snapshot of multiple aperture data collection is depicted enroute to building an image of an entire volume 310. Here, an element or elements of a transmit aperture T1 transmit a pulse into the volume that includes scatterers such as 321 and 322. The elements making up receive aperture R2 may be assembled in a variety of shapes. Here, a square of elements makes up the receive apertures R2 and R3. As mentioned above, the speed of sound along the path from the transmit aperture T1 to the reflector 321 or 322 is irrelevant to the coherent addition of the received signals as long as a single aperture is used to receive, however, speed of sound corrections can be made to improve image quality when using multiple receive apertures R1 and R2.

[0046] In some embodiments, the size of the receive aperture R2 may be as large as for a conventional phased array (e.g., about 2cm). But unlike a conventional array, the total aperture 340 determining the lateral and transverse resolution of the system is much larger comprising the distance from the transmitter T1 to the group of receiver elements R2, and could be as wide as the entire array 300 or wider if a transmitter was located on another array within the probe (or in a separate probe in electronic communication). The elements located in the receive aperture R2 each collect volumetric data from the T1 transmit pulse. Transmitter and receiver aperture sizes and sequences may be altered throughout the entire array, similar to the sequences described FIG. 2C, but now transmitters and receivers may be located anywhere within the array and in any axis.

[0047] Collecting data through varying tissue types naturally requires the accommodation of differing tissue acoustic impedance with differing speeds-of-sound. Pixel and voxel computations can only be accurate when these accommodations are made. U.S. Patent No. 9,146,313, titled "Point Source Transmission and Speed-of- Sound Correction Using MultiAperture Ultrasound Imaging" covers these methods in detail.

[0048] Imaging through bone, dense tissue (breast), lung or gas filled areas (pneumothorax) also come with challenges in handling the probe. Much like holding thepalm of your hand against a child’s forehead, holding an ultrasound probe that images into bone and lung should be as easy to hold up to the patient as the palm of your hand. This is the case represented in FIG. 3 A. Those familiar with the art will recognize that any plastic housing and convenient form factors can be designed. This particular housing was chosen to represent the fact that it could be easy in a trauma situation, by a relatively untrained person, who needed to image inside a skull for instance. The internal operations or arrays used in the probe, whether 2D as represented in FIG. 3C or 1.5D as represented in FIG. 3B, are not their concern.

[0049] Transmitting ultrasound energy into, and receiving reflected ultrasound energy from the tissue medium requires substantial respect for the acoustic nature and impedance of a variety of tissue types being imaged or scanned for non-imaging data. The mechanical design of the transducers and their associated matching layers, lenses, backing blocks and housings are well known to be critical in attaining the best signal. However, conventional ultrasound systems are primarily concerned with imaging “soft tissues’ like liver, kidney, heart, fetus and so forth. The speed-of-sound of these soft tissues is around 1540 m / s. Therefore, conventional imaging systems utilized the various mechanical inputs inside the transducer to “match” these speeds both on transmit and receive.

[0050] FIG. 4 then demonstrates a conventional ultrasound array designed to image into the human body, that can include a backing block 401, a piezo electric array 403, a 1st matching layer 405, a 2nd matching layer 407, and an acoustic lens 409. The backing block is at the rear of the transducer head and the lens actually touches the patient. Underneath the lens there are usually two metal, resin or RTV layers that are used to match the transmit pulse from the Piezoelectric array to the body. Similarly on receive, the matching layers speed up the echoes being received for registration as reflections on the elements of the piezo electric array. These pulses are then converted into digital signals through an analog to digital converter, and those signals are turned into ultrasound data and images. The backing block is used as a backstop for the piezo electric array. That is, on transmit the backing block “deadens” the transmission going backward to prevent transmit energy begin reflected back into the array. The majority of this energy would not be in phase with the transmitted energy and would result in degradation and or malformation of the outbound transmission leaving the face of the array. On receive, the backing block keeps the noise level lower for the array to both enable higher discernment of the receive transmission and lower cross talk between elements sharing the same ground.

[0051] FIG. 4 identifies some sample speeds-of-sound associated with the different layers. These numbers are for demonstration purposes of those consistent with aconventional ultrasound imaging array. Matching layers, backing blocks, lensing, all will vary in the types of materials use by different manufacturers and therefore the speeds-of- sound will also vary. However, in this example, the backing block has a speed of sound of 1900 m / s, the piezo electric array has a speed of sound of 5200 m / s, the 1st matching layer has a speed of sound of 2280 m / s, the 2nd matching layer has a speed of sound of 2050 m / s, and the acoustic lens has a speed of sound of 960 m / s.

[0052] Bone and Dense Tissue Imaging and Data Collection

[0053] This disclosure is concerned with building transducers that primary image or collect data from bone, dense tissue, lung or gas filled pockets. Then in collecting and utilized that data for both visual and non-visual diagnostic uses.

[0054] If we examine the hard tissues first, imaging inside the skull is a critical application. The skull, the speed-of-sound associated with the skull is 2050 m / s, quite a bit higher than other tissues in the body. Furthermore, other bones have even higher speeds of sound in the 2800-4080 m / s range. Therefore, providing matching down to 960 m / s as is the case in the conventional probe in FIG. 4 is not desired. Rather, providing matching down to 2050 m / s per second is desired. This matching enables the most energy into and through the skull. Getting energy into the soft tissue of the brain is what is truly desired. PMA systems beamform returning energy on the receive side only, and provide accommodations for differing acoustic density in that process. Therefore, getting acoustic energy into and out of the skull is the most important factor. Designing matching layers, lensing and backing blocks for piezoelectric arrays in both FIG. 5 and FIG. 6 demonstrate how that can be done. FIG. 6 utilizes two matching layers 415 and 417, whereas FIG. 5 uses only one matching layer 413. Furthermore, in the case of pMUT or cMUT arrays, no matching layers need be utilized. In those cases, transmission can be controlled with the ping based transmission of a PMA system, negating the need for matching layers and still delivering transmission in the 2050 m / s parameter.

[0055] FIG. 7 demonstrates a sample thickness of bone associated with the skull. Larger bones, such as the femur, ilium, lumbar vertebral body, may have even higher thickness and speeds-of-sound but are not shown here. If attempting to image inside these bones, penetrating and receiving data through the cortical bone is key. Arrays represented in FIG. 5 and 6 were designed for a “bone imaging probe” in order to provide clear images of the central structure of the bone.

[0056] Other embodiments of this device can be devised for other types of dense tissue (such as dense breast tissue, cancerous lesions, hardened plaque, etc.), especially when a physically smaller Multiple Aperture Transducer (e.g. IVUS, pediatric, transesophageal orintracavity guidance) is placed directly against these tissue types, or even to assist in tracking mechanical implements and catheters into hard tissue targets.

[0057] FIG. 8 demonstrates the materials and construction of a 3 array Multiple Aperture Probe, which can include higher speed or denser lens material closer to the speed of sound of the skull. The probe can include an injection molded nose piece and a RTV array buffer area to reduce intra array cross talk.

[0058] FIG. 9. demonstrates the location of higher speed matching layer locations on a desired probe for imaging through bone. As with the embodiment of FIG. 9, the probe can include higher speed or denser lens material closer to the speed of sound in the skull, an injection molded nose piece, and a RTV array buffer area to reduce intra array cross talk. The illustrated implementation can include two matching layers and a single array.

[0059] FIG 10. demonstrates the location of higher speed matching layer locations on a desired probe for imaging through bone. This implementation can include two matching layers and a single array with an injection molded nose piece with integrated lens. The nose piece with integrated lens can have a higher speed or denser material closer to the speed of sound in the skull.

[0060] Lung and Gas Filled Imaging and Data Collection

[0061] The adaptive beamforming characteristics of PMA systems also works on tissues with lower acoustic impedance and associated speeds-of-sound. Pulmonary parenchyma for instance typically has a speed-of-sound of 25 to 70 m / s.

[0062] In a lung base trauma situation, a transducer could be constructed to have a matching layer of 75 m / s at the skin surface. Utilizing the techniques described in FIG. 5 and 6, different matching layer materials could be utilized to further reduce the speed-of-sound. Furthermore, in the case of pMUT or cMUT arrays, no matching layers need be utilized. In those cases, transmission can be controlled with the ping based transmission of a PMA system, negating the need for matching layers and still delivering transmission in the 75 m / s parameter.

[0063] Adaptive Beamforming of Dense and Gas Filled Tissues Using Ping Based Multiple Aperture Systems

[0064] The physical apparatus and utilization of PMA transducers and equipment provides the ability to collect channel data from different aspect angles around the region of interest, all received data being collected from the same unfocused transmission. The process is described further in US Patent Application 2023 / 024833 titled “Multiple Aperture Imaging Systems and Methods” and US Patent Application 65 / 582,683 titled “Systems and Methods for Conducting Visual and Non- Visual Diagnostics Using Artificial Intelligence with MultipleAperture Ultrasound.” Beamforming, however, can be further modified to adapt for different tissue densities. For instance, optimum frequencies utilized to beamform bone in the skull may differ from the optimum frequencies to beamform brain or vascular tissue inside the skull. Similarly, strong reflectors (e.g. skull) providing higher voltage values can be associated and weighted and reduced, so that weaker reflectors beyond the strong reflectors (e.g. brain and vascular tissue) can be weighted an increased in value for better clarity.

[0065] In the case of brain imaging through the skull, a preferred embodiment is transmitted on one frequency, and receive on another frequency. For instance, transmitting on a low frequency and receiving on a higher fundamental frequency may be preferential to seeing only the soft tissue, if that is the desired area of interest. Using coded transmission may be helpful in also getting lower frequency transmissions more deep into the skull.

[0066] In the case of brain imaging through the skull, another embodiment is to interface a series of low frequency transmission sequences with a series of slightly higher frequency transmissions. This may be helpful in better identifying interfaces near the skull, such as the sub-dural space.

[0067] In a related but opposite manner, tissue beyond the pleura and inside the lung has an even lower speed-of-sound than the pleura and skin above it. Optimum frequencies utilized to beamform the pleura lining the outside of the lung may differ from the optimum frequencies to beamforming the pulmonary parenchyma inside the lung. Similarly, stronger reflectors (e.g. pleura) providing higher voltage echo values can be associated and weighted and reduced, so that weaker reflectors beyond the strong reflectors (e.g. pulmonary parenchyma) can be weighted an increased in value for better clarity.

[0068] This adaptive beamforming can be implemented in PMA systems and utilized with the transducers described herein for even more clear imaging of bone, dense tissue, lung and gas fdled tissue.

[0069] FIG. 11 shows a flowchart 1100 that describes a process for adaptive beamforming tissue that may be extremely dense, or gas fdled to improve contrast that may be relevant to diagnosis. Using a PMA system with Multiple Aperture Probe, the probe is placed over the region of interest. The system can be providing imaging data at the time per step 1101 or can be used without any imaging data being presented per 1102. Data may be collected in real-time, can be stored in system memory or even transmitted and stored in the cloud during step 1104 reference U.S. Patent No. 10,401,493, titled "Network-Based Ultrasound Imaging System.”

[0070] Step 1105 then provides the user the option of controlling subsequent steps using manual controls, or by selecting an automated process for optimizing each contributing data set. “Regions” are subsets of pixel or voxels also controlled by the user.

[0071] User controls are utilized to define a pixel or voxel region size. That is, the number of pixels to be analyzed together for pattern recognition is selectable by the user. This selectable pattern of pixels or voxels is called a region. FIG. 12, region 1200 shows a data set comprised of pixels or voxels, in this case as a 2D slice of pixels. The smallest possible region or grouping would be a single pixel, and the largest would be equivalent to the resolution of the system (e.g. 1260 x 1260 pixels). 1202, 1204, 1206 represent three pixel regions in FIG. 12. Each of 1202, 1204 and 1206 are using 6 by 3 pixels to define their regions. However, a typical selection could be on the order of 8 by 8 pixels. In a 3D system, the desired cube might be 8 by 8 by 8 voxels.

[0072] The initial values presented in Steps 1106 and 1108 are naturally produced as a function of beamforming in step 1104. Frequency and Voltage levels can then be adjusted by patterns of pixels or voxels, regions, independently and respectively in steps 1107 and 1109. That is, the user may adjust each of the data frequency and data voltage controls by region to achieve optimum differentiation and contrast between regions. This step may also be done automatically by engaging artificial or machine learning to optimize these parameters either by learning of the existing data set or by learning of a previously gathered and verified data set for that type of tissue.

[0073] The values used in Steps 1107, 1109 and 1111 are very important steps in the process because a single frequency or voltage threshold need not be selected for the entire data set. Optimum frequencies, voltage levels, or tissue density respectively, can be mapped onto the different regions of the data set to produce an image with optimum contrast and similarly an optimum data set for sub-visual utilization.

[0074] In one embodiment, beamforming in Step 1112 is usually done with only Frequency or Voltage data from Steps 1107 and 1109.

[0075] In another embodiment, beamforming in Step 1112 is further enhanced by using Frequency, Voltage and Acoustic Impedance from Steps 1107, 1109, and 1111.

[0076] The enhanced data set produced by the adaptive beamforming process can now be utilized to preset image data in Step 1118.

[0077] The data set produced by this enhanced adaptive beamforming process in Step 1122 may provide further clarity for data used in the sub-visual range.

[0078] Step 1126 illustrates that the process is repeated to continue to provide imaging and data sets using this process.

[0079] Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and / or uses of the invention and obvious modifications and equivalents thereof. Various modifications to the above embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.

[0080] In particular, materials and manufacturing techniques may be employed as within the level of those with skill in the relevant art. Furthermore, reference to a singular item, includes the possibility that there are plural of the same items present. More specifically, as used herein and in the appended claims, the singular forms "a," "and," "said," and "the" include plural referents unless the context clearly dictates otherwise. As used herein, unless explicitly stated otherwise, the term “or” is inclusive of all presented alternatives, and means essentially the same as the commonly used phrase “and / or.” It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as "solely," "only" and the like in connection with the recitation of claim elements, or use of a "negative" limitation. Unless defined otherwise herein, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Claims

CLAIMS1. A diagnostic ultrasound imaging method, comprising the steps of: transmitting an omni-directional unfocused ultrasound waveform into a target region with a transmit aperture of a multiple aperture ultrasound imaging probe; receiving ultrasound echoes from the target region with a plurality of receive apertures of the multiple aperture ultrasound imaging probe; with a processor of the multiple aperture ultrasound imaging probe, optimizing a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes; with the processor, beamforming the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance to obtain diagnostic 2D or 3D medical images; and presenting the diagnostic 2D or 3D medical images on a display.

2. The method of claim 1, further comprising repeating the optimizing and beamforming steps for additional regions of interest within the target region.

3. The method of claim 2, wherein the diagnostic 2D or 3D medical images include a plurality of regions of interest with varying frequency, voltage levels, and acoustic impedances based on the optimization for each region of interest.

4. The method of claim 1, wherein the processor implements a trained machine learning model to perform the optimizing step.

5. A diagnostic ultrasound imaging method, comprising the steps of: transmitting an omni-directional unfocused ultrasound waveform into a target region with a transmit aperture of a multiple aperture ultrasound imaging probe; receiving ultrasound echoes from the target region with a plurality of receive apertures of the multiple aperture ultrasound imaging probe; with a trained machine learning model of the multiple aperture ultrasound imaging probe, optimizing a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes;with a processor, beamforming the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance from the trained machine learning model to obtain diagnostic 2D or 3D medical images; and presenting the diagnostic 2D or 3D medical images on a display.

6. The method of claim 5, wherein the region of interest is received as a user input.

7. A diagnostic ultrasound imaging method, comprising the steps of: transmitting an omni-directional unfocused ultrasound waveform into a target region with a transmit aperture of a multiple aperture ultrasound imaging probe; receiving ultrasound echoes from the target region with a plurality of receive apertures of the multiple aperture ultrasound imaging probe; receiving an input from a user indicating a region of interest within the target region; with a trained machine learning model of the multiple aperture ultrasound imaging probe, optimizing a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes; with a processor, beamforming the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance from the trained machine learning model to obtain diagnostic 2D or 3D medical images; and presenting the diagnostic 2D or 3D medical images on a display.

8. The system of claim 7, wherein the trained machine learning model is configured to identify one or more patterns in the echo data.

9. The method of claim 7, wherein the trained machine learning model is configured to compare the one or more patterns to previously collected ultrasound echo data stored in a database.

10. An ultrasound imaging system, comprising: at least one transmitting transducer element configured to transmit an omnidirectional unfocused ultrasound waveform into a target region; a plurality of receiving transducer elements configured to receive ultrasound echoes from the target region;a processor configured optimize a contrast between voxels or pixels in a region of interest within the target region by adjusting at least one of a frequency, a voltage level, and an acoustic impedance of the received echoes, the processor being further configured to beamform the voxels or pixels in the region of interest with the adjusted frequency, voltage level, and / or acoustic impedance to obtain diagnostic 2D or 3D medical images.

11. The system of claim 10, further comprising a display configured to present the diagnostic 2D or 3D medical images on a display.

Images